INSECTS OF THE PLUM 283 



The frequent and thorough cultivation of the ground while 

 the pupa is still in the soil is of great value. The cultivation 

 should begin in the first part of July and continue to the first 

 of August in the north, but it must begin somewhat earlier 

 in the south. 



One of the earliest methods of control for the curculio was 

 by jarring. This method was the chief means of control for 

 many years and it is still practised extensively where only a 

 few trees are treated. In order to control the curculio by 

 jarring a sheet is first spread on the ground under the tree. 

 The tree is then suddenly jolted by hitting the trunk with 

 the end of a padded mallet. The beetles when suddenly 

 disturbed curl up and fall on the sheet and can then be col- 

 lected and destroyed. The jarring, to be the most effective, 

 should be done early in the morning when the beetles are less 

 active. 



The jarring has gradually been replaced by spraying in the 

 larger orchard because of the cheaper cost. 



The spraying with arsenate of lead either alone or com- 

 bined with a fungicide has now come to be the most favorite 

 method of controlling the curculio. The spraying of the 

 plum is somewhat more difficult than most of the other 

 fruits, but many growers believe that the result justifies the 

 practice. Two applications are usually made, the first soon 

 after the petals fall and the second from a week to ten days 

 later. Arsenate of lead applied at the rate of about 2| pounds 

 to 50 gallons is effective. This can be added to either lime 

 sulphur or a 2-2-50 Bordeaux mixture. 



OUTLINE FOR SPRAYING THE PLUM,. 



Number 



of spray. Time to spray. Spray materials. 



First Just before the blossoms open 4-4-50 Bordeaux mixture or 



lime sulphur 1 to 40. 



Second Just after the blossoms fall Commercial lime sulphur 1 to 



50 or self-boiled lime sul- 

 phur, plus 2 pounds arsen- 

 ate of lead to 50 gallons. 



Third Two weeks after the second Same as second. 



Fourth About the middle of June Same as second. 



Fifth Late July or early August Self-boiled lime sulphur or am- 



moniacal copper carbonate. 



